Installing a pre-hung door will add style and energy efficiency to your home while stopping drafts from coming through drafty areas. However, proper installation requires patience, good tools, and attention to detail.
Goal of hanging a door that operates smoothly, swings freely, and has an uniform reveal is to ensure it is installed at plumb and level with the frame. To do this successfully, it is important that all measurements of plumbness and levelness between door and frame be met before commencing installation of door.
Prepping the Rough Opening
Pre-hung doors with casing and jambs already attached are usually the best solution, saving time by eliminating the work involved in measuring and cutting both door and frame separately. Although pre-hung doors tend to cost slightly more than slab ones, they make life simpler by eliminating this step of installation altogether.
Starting off by inspecting the existing opening. It should be two to two-and-a-half inches wider than your door. If the head and side jambs don’t line up perfectly with one another, add shims as necessary in order to square them off.
Set a 4-foot level against the floor in the jambway. If the level’s bubble is centered in the lower frame part, no further adjustment should be required. If necessary, slip shims under and adjust them until their bubble centers on its location in the doorway framing; secure these with finishing nails or screws once adjusted.
Installing the Jambs
Prehung doors typically come equipped with split jambs, which means they attach to both parts of the main jamb and feature an additional piece for holding back doors. Begin by attaching hinge side of frame using wooden shims for leveling and stabilization purposes.
Once the jamb is secure, use a 4-foot level to check that the gap between door jamb and frame is even. Make sure the bubble on hinge side of level is centered. Shim the latch side as necessary to achieve balance.
Shimming the frame until its reveal at the top of the door is even. Use a nail gun or screw gun with #8 screws (for wood frames) or #6 screws (for metal ones) at each shim location to fasten it to the studs, fastening to each stud using fasteners at each location shimmed.
Shimming the Door
When installing an inswing door, make sure the necessary hardware (backplates, doorknob and strike plate) are in place prior to mounting the casing. This ensures proper alignment between backplates, doorknob and strike plate and the frame.
Once the hinge side has been properly shimmed and levelled, close and check that the latch jamb does not sit below the head jamb; if that is indeed the case, additional shimming on this end may be required as well.
Shimming both sides of the frame as needed to make it square with wall studs requires several shims; then using finish nails through all shims into wall studs with finish nails will complete this step. If necessary, trim off excess material if the frame was off by much. If any shims stick out beyond what is acceptable by scoring or breaking off with a utility knife.
Hanging the Door
Check your door frame using a level to make sure it’s plumb with the floor, using shims if necessary to raise one side until it evens out with its counterpart (stop block or stop block, depending on its name).
Have someone hold the door in its frame, hinge-side up, while you mark around its hinge plate position on both frames – hinge side and latch side of each one.
Place a 4-foot level on the floor in your doorway. If the level bubble is centered between hinge and latch jambs, pre-hung doors may be suitable. Otherwise, add shims between the floor and bottom frame until bubble is centered – then secure and tighten hinges as necessary.
Installing interior or exterior doors is an excellent way to increase energy efficiency, boost security and boost curb appeal in your home – but this project does require basic carpentry knowledge when installing the jambs.
Pre-hung doors differ from slab doors in that they already come complete with hinges and frames attached, along with cutouts for doorknobs. Pre-hung doors tend to cost more, but save both time and effort during installation.
Installation of pre-hung doors relies heavily on accurate measuring tools like a level and tape measure, to ensure their frames are level, plumb, and flush with the wall drywall surface. Shimming may help if necessary to make this possible – caulk the trim and enjoy your new door!